Spectrum™ Iodoquinol, Powder, USP Also known as Diquinol and iodoxin, is used in the treatment of amoebiasis and as a luminal amebicide. The USP grade indicates it is graded suitable for personal care, cosmetic and pharmaceutical applications. All Spectrum Chemical manufactured USP grade products are manufactured, packaged and stored under current Good Manufacturing Practices (cGMP) per 21CFR part 211 in FDA registered and inspected facilities.